JPS6033145B2 - recording liquid - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a novel recording liquid, particularly a recording method in which recording is performed by ejecting the liquid from fine ejection ports (ejection orifices) provided in a recording head and flying it as droplets. Regarding recording liquid suitable for.

2. Description of the Related Art Conventionally, writing instruments (fountain pens, felt pens, etc.) for recording on recording materials such as paper have used inks prepared by dissolving various dyes in water or organic solvents.

Furthermore, in the so-called inkjet recording method, in which recording is performed by ejecting liquid in the recording head from an ejection orifice using vibrations caused by a piezo vibrator or electrostatic attraction caused by the application of high voltage, various dyes are mixed with water or organic solvents. It is known to use compositions dissolved in, etc.

However, compared to inks for stationery such as general fountain pens and feltbens, inkjet recording liquids require more stringent conditions for many characteristics. In this way, the inkjet recording method uses droplets of recording liquid called ink (
Recording is performed by flying a droplet and attaching it to a recording material.

Such a recording liquid is a recording agent (dye or pigment is used).
The basic components are a liquid medium (water, various organic solvents, or a mixture thereof) for dissolving or dispersing this, and various additives are added as necessary. There are various types of such recording methods depending on the method of generating droplets and the method of controlling the flight direction of the droplets.

An example is shown in FIG. The apparatus shown in FIG. 1 performs recording by applying a recording signal to a recording head having a piezo vibrator and generating droplets of recording liquid in response to the signal.

In FIG. 1, the recording head 1 includes a piezo vibrator 2a,
It has a diaphragm 2b, a recording liquid inlet 3, a liquid chamber 4 in the head, and an ejection port (ejection orifice) 5. A recording liquid 7 stored in a storage tank 6 is introduced into the liquid chamber 4 through a supply pipe 8 . Note that an intermediate treatment means 9 such as a pump or a filter may be provided in the middle of the supply pipe 8 depending on the case. The piezo vibrator 2a receives a recording signal S by a signal processing means (for example, a pulse converter).
A signal converted into a pulse is applied, and a pressure change occurs in the recording liquid in the liquid chamber 4 in accordance with the signal. As a result, the recording liquid 7 is discharged from the discharge orifice 5 in the form of droplets 11, and recording is performed on the surface of the recording material 12. In addition, various types of devices are known in addition to the devices described above. For example, as shown in FIG. 2, as a modification of FIG.
There is a device in which a cylindrical piezoelectric vibrator is installed around the outer periphery of a nozzle-shaped liquid droplet (the mechanism for generating droplets in this device is essentially the same as the device shown in Figure 1). , and a device that continuously generates charged droplets and uses a portion of the droplets for recording.

Alternatively, an apparatus is known in which thermal energy corresponding to a recording signal is applied to the recording liquid in the recording head chamber, and the energy is used to generate droplets. An example of a device that utilizes this thermal energy is shown in FIGS. 3-a, 3-b, and 4.

The recording head 13 is made of a glass, ceramic or plastic plate having grooves 14 through which ink passes, and a heat generating head 15 used for thermal recording (a thin film head is shown in the figure, but is not limited to this). Obtained by gluing.

The heating head 15 includes a holding film 16 made of silicon oxide or the like, aluminum electrodes 17-1, 17-2, a heating resistor layer 18 made of nichrome or the like, a heat storage layer 19, and a substrate with good heat dissipation such as alumina. It consists of 20 pieces. ink 2
1 has reached the discharge orifice 22, and a meniscus 23 is formed by the pressure P. When an electric signal is applied to the electrodes 17-1 and 17-2, the area indicated by n of the heating head 15 suddenly generates heat, bubbles are generated in the ink 21 in contact with this area, and the meniscus 23 protrudes due to this pressure. , the ink 21 is ejected from the orifice 22 into a recording passageway 24, and is blown onto the recording material 25.

FIG. 4 shows an external view of a multi-head in which a large number of heads shown in FIG. 3-a are arranged. The multi-head has multi-groove 2
6 and a heat generating head 28 similar to that described in FIG. 3-a are bonded together. Note that FIG. 3-a is a cross-sectional view of the head 13 along the ink flow path, and FIG. 3-b is a cross-sectional view taken along line A-B in FIG. 3-a.

Conventionally, as this type of recording liquid, for example, Japanese Patent Publication No. 50-83
No. 61, Special Publication No. 51-40484, Special Publication No. 52-13
No. 126, Special Publication No. 52-13127, Japanese Patent Publication No. 50-9
As shown in No. 5008, dyes or pigments in which various dyes or pigments are dissolved or dispersed in aqueous or non-aqueous solvents are known.

Preferred conditions for this type of recording liquid include: 1. Liquid physical properties (viscosity, surface tension, electrical conductivity, etc.) that match the ejection conditions (piezoelectric element drive voltage, drive frequency, orifice shape and material, orifice diameter, etc.). have.

2. Stable and non-clogging for long-term storage.

3 The fixation is far away from the recording material (paper, film, etc.)
The area around the dots is smooth and the bleeding is 4.

4 The printed image has clear color tone and high density.

5. The printed image has excellent water resistance and light resistance. 6. Recording liquid should not corrode surrounding materials (containers, connecting tubes, sealing materials, etc.).

7. Must have excellent safety features such as odor, toxicity, and flammability.

etc.

It is quite difficult to simultaneously satisfy the above characteristics, and the prior art described above was unsatisfactory in this respect.

Since the recording liquid used for recording for such purposes is basically composed of a dye and its solvent as described above, the characteristics of the recording liquid are influenced by the inherent properties of the dye. is large.

Therefore, selecting a dye so that the recording liquid has the above-mentioned properties is an extremely important technique in this technical field. As a result of extensive research, the present invention was completed by finding and developing a dye suitable for the recording liquid used for this purpose.

That is, the recording liquid of the present invention is a recording liquid containing a recording agent as a component forming the recording liquid and a liquid medium for dissolving or dispersing this recording agent.
: [In the formula, Y represents any one of a hydrogen atom, a methyl group, a methoxy group, an acetylamine group, and a nitro group, and may form a benzene ring together with the carbon atom at the 3-position of the benzene ring B.

On the other hand, × is an acetyl group, a benzoyl group, a valatorenesulfonyl group, a 4-chloro-6-hydroxy-1,3,5
, triazin-2-yl group, and M
1, M2, and FOL are bases selected from alkali metals, ammonium, and amines, respectively. ) is characterized in that it contains at least one type of dye represented by:

Specific examples of the dye represented by the general formula [A] applicable to the recording liquid of the present invention include those shown in Table 1 below.

Satofune: These dyes exhibit superior performance in meeting the above-mentioned required properties compared to previously known dyes with similar structures.

For example, a recording liquid containing a dye represented by the general formula [A] as a recording agent has a lower light fastness than a print obtained using a recording liquid containing the following dye 1) as a recording agent. It is excellent in In addition, when compared with a recording liquid containing the following dye (3) as a recording agent, it shows clear superiority in that it is stable for long-term storage and does not cause clogging of the discharge orifice. (C.1. Reactive Drop-35) (C.1. Reactive Drop-17) The dye represented by the general formula ◯, that is, the monoazo compound applied to the recording liquid of the present invention, is a monoazo compound having the above-mentioned structural formula ○}.
It can be produced by the same method as dyes represented by and (■) or dyes having structures similar to these,
For example, "R Theory Manufacturing Dye Chemistry" written by Yutaka Hosoda (July 15, 1960, published by Gihodo), p. 580, lines 5-11, or "New Dye Chemistry" written by Yutaka Hosoda (December 21, 1960, published by Gihodo),
Published by Gihodo) Page 441, No. 2 Mochimori - No. 442, No. 126
It can be manufactured by a method similar to that described in .

That is, the following general formula (wherein, Y represents the same meaning as above).

) is diazotized using sodium nitrite, etc. in salts, dilute mineral acids such as sulfuric acid, and then the following general formula {
C} (wherein, x represents the same meaning as above.

) can be easily produced by coupling reaction with naphthols represented by: According to the present invention, physical property values such as viscosity and surface tension are within appropriate ranges, do not clog fine orifices, provide recorded images with sufficiently high density, and prevent changes in physical property values during storage or solid content. A recording liquid that does not cause precipitation, can record on various materials without limiting the type of recording material, has a high fixing speed, and provides images with excellent water resistance, light resistance, abrasion resistance, and resolution. is obtained. Such a recording liquid can be prepared as follows.

The color component, that is, the content of the dye represented by the above general formula, is determined depending on the type of liquid medium, the characteristics required of the recording liquid, etc., but is generally expressed as a percentage by weight based on the total weight of the recording liquid. The range is 0.1 to 20%, preferably 0.5 to 15%, more preferably 1 to 10%. Of course, these dyes can be used alone, in combination of two or more, or in combination with other direct dyes or acid dyes.
Water or a mixture of water and various water-soluble organic solvents is used as a liquid medium component for forming the recording liquid.

Examples of lagoonal organic solvents include methyl alcohol, ethyl alcohol, and n-fluoride. Lopinorea ``record'' le, isof. carbon number 1 or more, such as ropi/real alcohol, n-butylene alcohol, set-buty/real alcohol, rt-butyl alcohol, isobutyl alcohol, etc.
Alkyl alcohols of No. 4; Amides such as dimethylformamide and dimethylacetamide; Ketones or ketone alcohols such as acetone and diacetone alcohol; Tetrahydres. Ethers such as furan and dioxane; Nitrogen-containing heterocyclic ketones such as N-methyl-2-pyrrolidone and 1,3-dimethyl-2-imidazolidinone; Polyalkylene glycols such as polyethylene glycol and polypropylene glycol; ethylene glycol , alkylene glycols in which the alkylene group contains 2 to 6 carbon atoms, such as propylene glycol, butylene glycol, triethylene glycol, 1,2,6-hexatriol, thiodiglycol, hexylene glycol, and diethylene glycol; Glycerin; Examples include lower alkyl ethers of polyhydric alcohols such as ethylene glycol methyl ether, diethylene glycol methyl (or ethyl) ether, and triethylene glycol monomethyl (or ethyl) ether. Among these many water-soluble solvents, polyhydric alcohol diethylene glycol, lower alkyl ether of polyhydric alcohol triethylene glycol monomethyl (or ethyl) ether, etc. are particularly preferred from the viewpoint of preventing clogging.

The content of the water-soluble organic solvent in the recording liquid is generally 5 to 95% by weight, preferably 10% by weight based on the total amount of the recording liquid.
The range is 80% to 80%, more preferably 20 to 50%.

The water content at this time is determined within a wide range depending on the type of solvent component, its composition, or the desired properties of the recording liquid, but is generally 10 to 90% of the total weight of the recording liquid.
%, preferably 10-70%, more preferably 20-7
The range is 0%.

A recording liquid prepared from such components has its own recording properties (signal response, stability of liquid bottle formation, ejection stability, etc.).
long-term continuous recording performance, ejection stability after long-term recording pauses) retention stability, fixation to the recording material, and recorded image light resistance, weather resistance, water resistance, etc. It is excellent.

In order to further improve such properties, various additives known from the field of manufacture may be further included. For example, viscosity regulators such as polyvinyl alcohol, celluloses, and water-soluble resins; various cationic, anionic, or nonionic surfactants; surface tension regulators such as jetanolamine and trietanoamine; PH regulators using buffers;
Antifungal agents and the like can be mentioned. Further, in order to prepare a recording liquid used in an inkjet recording method of the type in which the recording liquid is charged, a resistivity adjuster such as an inorganic salt such as lithium chloride, ammonium chloride, or sodium chloride is added.

Note that when applied to an inkjet system in which recording liquid is ejected by the action of thermal energy, thermal physical property values (eg, specific heat, coefficient of thermal expansion, thermal conductivity, etc.) may be adjusted.

The present invention will be explained in more detail with reference to the following Examples and Reference Examples. Reference example 1 [No. Synthesis of dye 1] Orthanilic acid (o-aminobenzenesulfonic acid) 17.
The mixture was added to 346 cc of 3% hydrochloric acid and stirred for 3 hours to form a uniform slurry.

200 g of ice was added to this to cool it to 3°C. Separately, 7.3 mL of sodium nitrite was dissolved in 73 cc of water, and this was added to the slurry. After diazotization by stirring at 3° C. for 1 hour, remaining sodium nitrite was eliminated by adding sulfamic acid.

On the other hand, 42.3 g of N-penzoyl dihydrochloride was added to 850 cc of water, and then 20 cc of 25% caustic soda aqueous solution was added.
H was dissolved at 9.

Add 800 g of ice to this to bring the temperature to 3°C, then add the diazo solution, 200 g of ice and 35 cc of 25% caustic soda to pH 8-
10. Coupling was carried out by alternating additions while maintaining the temperature at 2 to 5°C. After boiling for 5 hours at the same temperature, add 500 salt
The product was salted out by adding water. The precipitated product was filtered and washed with 500 cc of 20% saline to obtain a wet cake. After desalting this wet cake, it was dried and No. 1 dye was obtained. The results of elemental analysis were as follows.

Reference example 2 [No. Synthesis of dye No. 2] 3% of 4-aminotoluene-3-sulfonic acid 18.7%
The mixture was added to 380 cc of hydrochloric acid and heated for 3 hours to form a uniform slurry.

200 g of ice was added to this to cool it to 3°C. Separately, 7.3 mL of sodium nitrite was dissolved in 73 cc of water, and this was added to the slurry. After diazotization by stirring at 3° C. for 1 hour, remaining sodium nitrite was eliminated by adding sulfamic acid.

After adding 42.3 g of N-penzoyl dichloride to 850 cc of water, 20 cc of 25% caustic soda aqueous solution was added to adjust the pH to 9.
It was dissolved as Add 800 g of ice to this to bring the temperature to 3°C, then add the diazo solution, 200 g of ice and 4 ml of 25% caustic soda.
Coupling was performed by alternately adding 0 cc of the solution while maintaining pH 8-10 and temperature 2o-5°C. After heating at the same temperature for 5 hours, 500 g of common salt was added to salt the product. The precipitated product was filtered and washed with 500 cc of 20% saline to obtain a wet cake. After desalting this wet cake, it was dried and No. 52.2 ml of dye 2 was obtained. The results of elemental analysis were as follows.

Reference example 3 [No. Synthesis of dye No. 7] Tobiasic acid (8-naphthylamine sulfonic acid) 22.3
The slurry was added to 450 cc of 5% hydrochloric acid and stirred for 3 hours to form a uniform slurry.

300 g of ice was added to this to cool it to 3°C. Separately, 7.3 mL of sodium nitrite was dissolved in 73 cc of water, and this was added to the slurry. After diazotization by heating at 3° C. for 1 hour, remaining sodium nitrite was eliminated by adding sulfamic acid.

After adding 36.1 ml of N-acetyl dinic acid to 750 cc of water, 20 cc of a 25% caustic soda aqueous solution was added to adjust the pH to 9 and dissolve the mixture.

After adding 800 g of ice to this and bringing it to 3°C, the diazo liquid,
200ml of ice and 70cc of 25% caustic soda pH 8-1
Coupling was carried out by alternating additions while maintaining the temperature between 0.0°C and 2°C to 5°C. After boiling for 5 hours at the same temperature, add 500 salt
The product was salted out by adding water. The precipitated product was filtered and washed with 500 cc of 20% saline to obtain a wet cake. This wet cake was desalinated and then dried to obtain No. 47.1 of the dye No. 7 was obtained. The results of elemental analysis were as follows.

Example 1 The above components were thoroughly dissolved in a mixture in a container, and the pore size was 1 mm.
After pressure filtration with a Teflon filter, the solution was degassed using a vacuum pump to obtain a recording liquid.

Using the obtained recording liquid, a recording device having an on-demand recording head (discharge orifice diameter 50 m, piezo oscillator drive voltage 60 V, frequency cycle 2) that ejects the recording liquid by a piezo oscillator is used. , below (T,) ~ (T
When 5) was investigated, good results were obtained in all cases. (T,) Long-term storage stability of the recording liquid: Even after the recording liquid was sealed in a glass container and stored at 130qo and 6000 for 6 months, no precipitation of unresolved components was observed.
There was no change in the physical properties or color tone of the liquid.

(L) Ejection stability: Two continuous ejections were performed in an atmosphere of room temperature, 5° C., and 4,000 ℃, and stable high-quality recording was possible from beginning to end under all conditions.

(T3) Intermittent ejection every 2 seconds and ejection after being left for 2 months were measured, and in both cases, there was no clogging at the tip of the orifice, and the recording was stable and uniform.

(T4) Quality of recording lines; The recorded images had high density and clarity.

After 3 months of exposure to room light, the density reduction rate was less than 1%, and when immersed in water for 1 minute, there was very little smearing of the image. (L) Fixability for various recording materials: For the recording materials listed in the table below, the presence or absence of image shift and bleeding was determined by rubbing the sand/rear print area of Printing No. 19 with a finger.

All of them exhibited excellent fixing properties with no image shift or blurring. Example 2 A recording liquid having the above composition was prepared in the same manner as in Example 1, and an on-demand type multi-head (discharge Orifice diameter 35 m, heating resistor resistance value 150
Similar to Example 1, studies (T,) to (T5) were conducted using a recording device with a drive voltage of 30 V and a frequency order of HZ, and excellent results were obtained in all the study experiments. Ta.

Example 3 A recording liquid with the above composition was prepared in the same manner as in Example 1, and an on-demand type multi-head ( (T,) to (L) as in Example 1 using a recording device having a discharge orifice seat of 35 m, a heating resistor resistance value of 1500, a drive voltage of 30 V, and a frequency of HZ).
We conducted a study on this, and obtained excellent results in all the study experiments.

Example 4 A recording liquid having the above composition was prepared in the same manner as in Example 1, and an on-demand type multi-head (discharge orifice Diameter 35 mm, heating resistor resistance value 150
Using a recording device with a drive voltage of 30 V and a frequency of 0.0 V, a driving voltage of 30 V, and a frequency of HZ, we carried out studies on (T,) to (T5) in the same manner as in Example 1. Obtained.

A recording liquid having the above composition was prepared in the same manner as in Example 1, and an on-demand type multi-head (
Discharge orifice diameter 35 m, heating resistor resistance value 1500
Similar to Example 1, studies (T,) to (T5) were conducted using a recording device having a drive voltage of 30 V and a frequency of 2 KHZ, and excellent results were obtained in all the study experiments.
Examples 6 to 10 Recording liquids having the compositions shown in 610 below were prepared in the same manner as in Example 1.

These compositions were filled in feltbens and written on medium-quality paper (Hakubotan: Honshu Paper Industries) to examine water resistance and writability after being left for 24 hours with the cap removed. The recording liquid of this example was excellent in both water resistance and writability after standing.

In addition, in Example 6, No. 17 Dye Substitute MokoN
o. 4, 5, 6, 7, 8, 9, 10, 11, 12, 14
, 15, 16, 18, 19, 20, 21, and 23 were used to prepare recording liquids, and good results were obtained in all cases.

[Brief explanation of the drawing]

FIG. 1 and FIG. 2 are schematic diagrams of an inkjet recording apparatus, respectively. Figures 31a and 3-b are a vertical sectional view and a horizontal sectional view of a main part of another recording device. Figure 4 shows Figure 3-a, Figure 3.
FIG. 3 is an external perspective view of a multi-layered head shown in FIG. 1... Recording head, 2a...
Piezo vibrator, 2b... Vibrator, 3... Inflow port, 4, 1
4...liquid chamber, 5...discharge orifice, 6...
・Storage tank, 7...Recording liquid, 8...
Supply pipe, 9... Intermediate processing means, 10... Signal processing means, 11... Droplet, 12, 25... Recording material, 15... Heat generation Head, 16...
・Protective layer, 17... Electrode, 18... Heat generating resistor layer, 19... Heat storage layer, 20...
- Substrate, 26...groove, S...recording signal. Zero limit Figure 2 Figure 3 - △ Figure 3 -. Illustration of hair 4

Claims (1)

[Claims] 1. In a recording liquid containing a recording agent as a component forming the recording liquid and a liquid medium for dissolving or dispersing this recording agent, the recording agent is represented by the following general formula (A); There are mathematical formulas, chemical formulas, tables, etc.▼ [In the formula, Y represents a hydrogen atom, a methyl group, a methoxy group, an acetylamino group, or a nitro group, and together with the carbon atom at the 3-position of the benzene ring B, benzene Sometimes they form a ring. On the other hand, X is an acetyl group, benzoyl group, para-toluenesulfonyl group, 4-chloro-6-hydroxy-1,3,5
,-triazin-2-yl group, and M
^1, M^2, and M^3 are each a base selected from alkali metals, ammonium, and amines. ] A recording liquid characterized by containing at least one kind of dye represented by the following. 2. The recording liquid according to claim 1, wherein the dye represented by formula (A) is contained in an amount of 0.1 to 20% by weight based on the total weight of the recording liquid.